Category: VHF

It appears that the International Space Station (ISS) was transmitting slow scan television (SSTV) off and on for the past couple of days. The Russian ARISS team was transmitting images commemorating the 80th birthday of Yuri Gagarin, the first human to orbit earth. It was being transmitting from the Russian service module using only 5 watts of power. I wanted to see if I can get one of these images on my own. They were using 145.800Mhz as the downlink frequency so at least I have the radio for it.

It was advertise that they were going to be transmitting on December 20th starting around 12:40z and will end around 21:30z . So from about 7:40am to 4:30pm locally which is almost a 9hr run. Due to its orbit, it only allows me a couple of chances to receive the transmissions

Due to work schedule, I was not going to make the 17:17z pass so I concentrated at 18:52 because the elevation would put the ISS right over my house instead scanning the horizon. It was my best chance.

At around 1:00pm, I made sure everything is in working order. The equipment I was going to use was a Radio Shack police scanner, Elk antenna, my laptop with a USB sound card, audio patch cable and the software MMSSTV. At around 1:30 I took everything to the much colder outside and setup shop. Now that I think back, I should have also setup my home 2M using the vertical antenna on my roof to decode as well.

I stated waving the antenna around at 1:50 and finally around 2pm is when I started hearing the ISS. If you want, you can watch the following video. Please ignore everything wrong. I thought of recording it last second and would have at least not wear my work clothes.

Once I locked onto the ISS, It was already too late. The ISS was already transmitting an image. But I was able to decode the majority of the image

That’s not bad. All I am missing is the RS0ISS header which is the callsign used by the Russians on the space station.

I had a blast doing this. It was really fun and I hope NASA and Roscosmos would do more things like this in the future. It could really encourage people to join into the amateur radio community.

It’s been a couple weeks since field day (FD) and I finally got around to writing something about my experience. For the past 4 years I’ve been doing field day with one of the local ham clubs. My first year I was a digital station and then for the past 3 years I’ve been the 40M SSB station in a 5 (or) 6A setup. The HCRA puts on an impressive field day with 50′ portable towers, beams and wire antennas. It’s amazing to see a lot of the area hams come together and work for this one weekend. It’s something that I look forward to doing every year since before I was ever licensed.

In my first year running the 40M SSB station, I treated it like a contest even though it’s not really a contest. After looking back it, I treated some people very poorly because either they weren’t making contacts fast enough, calling long when there was a pileup and other things. Field day is meant to attract people to operating, not scare them away. So for the past couple of years, I made sure that other people got to operate with as little pressure as possible. It’s about having fun and not the rates of contact. The only time I would jump on the air is if there was no operators available and only then would I try to beat any personal goals.

This year was much better and felt that it was one of the best field days I’ve been a part of. Everyone seemed to leave happy and one potential ham had a great time racking up over 100 contacts. He went from being almost afraid and hesitant, to running on a frequency and holding his own.

The Icing on the cake however was making contact with the ISS. During field day Astronaut Gregory Weiseman (KF5LKT) was using the NA1SS callsign making contacts on 2M. The first pass of the ISS was approx 20M into field day. Kiley (K2KHA) managed to make contact with the ISS using the club call but we were informed that the contact didn’t count for as a SAT contact for field day so on the next pass we we’re going to line up and use our own callsigns. I lost track of time and was on the air when the next pass came. I looked up and saw people making contact so I jumped out of my seat and ran over.

Here I am making contact with the ISS.

(Credit to: Matt Williams, W2MDW)

You can see that I am still in field day mode and didn’t understand how Sat/ISS contacts are made but it still counts. We all lined up to make contact before the pass was lost.

I had some time to myself on Saturday (6/14) which is rare so I decided to play a little radio on top of a mountain/hill. I found that when it comes to doing SOTA that ends up being a last minute effort to get my stuff ready. This time I wanted to do a summit that I have never done before. I decided to go to Peaked Mountain located in Hampden/Monson MA. I notified SOTAwatch and local SOTA/Ham facebook groups that I will be out. I find that letting many people know that you’re going to be activating will increase your chances of a successful activation.

The Hike

Expecting the unknown for both the hike and summit I over packed which is better than not packing that one item you’ll end up needing. The mountain is closer to my QTH then I originally thought which was great. The hike also wasn’t bad. The trails were (now) clearly marked and was able to make it to the summit in 20min or so. My only concern was the rain.

Welded Sign/Box near the summit

The Setup

Due to the overcast I didn’t have much time to really enjoy the view. I wanted to get on the air as fast as possible in case it was going to rain. However I have a new G5RV jr that I home brewed to replace the crappy G5RV that I was using. I also took along the vertical end fed (EARCHI) as I’ve never used it for SOTA. I wanted to put both up.

Here you can see the G5RV mounted to the Jack Kite 31′ fiberglass pole. I used an eyebolt that is connected to the center insulator and slid it down the mast. I might place some tape at that spot to keep the eyebolt from wearing out the fiberglass tube. Also pictured is the end fed that is attached to the tip of the pole.

Another photo showing my mini G5RV. I made custom insulators using plexiglass that doubles as winders

Here is a photo showing my old G5RV next to my new one.

Here is a shot of the antenna with both antennas attached.
Setup took less than 10Min with most of my time spent untangling wires.

Getting On The Air

After sending out a spot to SOTAwatch and my local SOTA group I was on the air. However no one is coming back. Usually I get people within minutes coming back to my crys of CQ. After about 10min or so, Jim (KK1W) came back to my crys and made my first contact. Other people started to trickle in. After AJ5C and N4LA I heard a couple DX contacts from Romania and England but was un-able to establish contact

My setup with the KX3, Wouxun for VHF and my 9:1 match for the endfed

I tried switching around bands and antennas to make my contacts. I knew I could make contact with KB1RJC and KB1RJD if I went onto 40M and sure enough they were on and waiting (thank you). They made my 4th and 5th contact.

My Seat with Antenna in the background

After making a couple more local contacts, I called it a day. I have 7 contacts so I can consider the summit to be officially activated. The sun started to come out and the skys started to clear up a bit and was able to enjoy the view from the mountain top

Views from the top of Peaked Mountain.

Overall Experiences

I’d say this was the hardest HF activation I’ve done to date. It was not the hike because that was very nice and easy. It was hard because I am not sure if it was my antennas, location, band conditions or a combination of all three that was making it difficult for communicating. There were also many hikers up on the mountain and I ended having to explain “what that is” many times over which took me away from the radio. Even though I love explaining what my setup is to non-hams, I just wasn’t in the mood but I didn’t want to come off as rude. I love the location and mountain and this location is now on my list of summits to activate next year.

I’ll be honest and say that I laughed when I saw the Yaesu FT-817 for the first time when it was released in 2001. “You’re not going to make any contact with that! It’s small and only 5 watts! No one is going to hear you!” I recall saying a lot. I like to note that I was brand new to amateur radio and had no HF experience. I thought it was silly to “talk” around the world with the same amount of power that my handheld VHF puts out. Well… 12 years later and they are still being produced and sold. I’ve seen the error of my ways and accept that QRP (low power) contacts are very possible. Now that I’ve been involved with HF for about 4 years now, I can see how rewarding QRP contacts are. Now that I’m more involved with SOTA (summits on the air), doing a bunch of VHF SOTA activations and watching my peers on HF, I decided to purchase a portable HF rig.

I ended up going with the Elecraft KX3.

I could have went with the much cheaper FT-817 and other QRP Xceivers but the features and technology of the KX3 far surpass what the FT-817 had to offer. Well… at least in writing. I just wanted something NEW for a change. Even though the KX3 is expensive, I cheaped out as much as possible and got the kit version of the KX3 with no options or extra accessories.

Hopefully the postal carrier didn’t notice me peeking through the windows with the excited look on my face as he approached.

There are already dozens, if not hundreds of videos, blogs, forum posts of assembling the KX3. I am not going to go into detail here. However I would like to share some notes and tips if you were to get the kit. Most are common sense.

Spend time and make sure every nut, screw, standoff and part is in the kit! Use muffin tins or a tackle box to keep parts separate.

Do not be surprised if your missing something. They include an extra parts bag and hopefully it’s in there.

Read the assembly manual entirely before starting. Do not jump ahead!

It’s not a contest, take your time and confirm each step

Besides a screw driver and other basic hand tools. I strongly suggest in using tweezers or a “Jewelers Pickup Tool”

This tool helped me out as the tiny 2-56 screws were a wee bit hard to handle.

The only issues I had were installing the plastic battery holders (which is noted in the manual) and having to deal with missing 4-40 screws. luckily I had anodized screws in my personal extra screw bin. Overall the assembly went okay and it took about 2 hours. Is it worth the extra $100 for an assembled kit? All depends on how you value your time. Think of it costing $50/hr for assembly. Are you worth more than that?

First thoughts

After turning it on, one of the first things I did was to compare the receivers of the KX3 to my FT-950 using a switch and the G5RV antenna. Since I don’t have any type of equipment that will give accurate readings, I am basing my findings from what I’ve seen and heard. On SSB, it seemed to receive similar with the DSP turned on in the 950 (No DNR). It has similar S-Unit readings. However the KX3 felt like it dealt with adjacent signals better than the 950. On CW, it seemed the KX3 was better at receiving.

Should Have Purchased Options

Like usual, I was being cheap and purchased the KX3 as a kit without any options. For some people that would work just fine. If you have a spare microphone and resonate antennas at the frequencies you want then you might not have a need for options like the ATU (Automatic Antenna Tuner) or microphone. But here I am with no microphones and no resonate antennas. I could have purchased an Emtech ZM2 or Hendricks SOTA tuner and a used microphone online that would have done just fine, but I didn’t want to lug around more equipment and didn’t want to modify the microphone. I ended up purchasing the ATU and Microphone from elecraft a short time later.

Issues with the KX3

I’ve held off writing this article for a long time because I had issues with my KX3. After assembly and before installing the ATU, I was hot to trot. I went on the air, started sending out CW to see what skimmers (bots) were picking up my signal. I couldn’t transmit at full power. Even with the KX3 powered using an External 5amp supply, I could not get past 7W. When using batteries, I saw 3watts max. Putting blame on my antenna at first I didn’t think much of it. At this point I decided it was best to order the ATU as I would end up using compromised antennas like an end fed or random wire where needing a “tuner” (match) would be important. When I received and installed the ATU, I noticed that I couldn’t tune correctly and it was still folding back power. After taking it out on it’s first SOTA activation, I knew something was wrong.

Dealing with Elecraft

I knew it had to be fixed. The first stop was the Elecraft KX3 Yahoo Group to see if anyone else had similar issue. None were found so after following the advice on Elecraft’s website, as requested, I contacted them VIA e-mail.

I’ve heard that Elecraft support was AMAZING!! However I felt the opposite. Just to get a reply from Elecraft took me well over a week. I ended up finding e-mail addresses to some of the staff/support members for Elecraft and after contacting them, my issue was finally looked at. It felt like I had to be pushy and demanding to get stuff done which is not a part of who I am so it was uncomfortable. However I just spent a lot of money, for some it may be nothing but it was a lot of saving on my part so I felt cheated a bit even though Elecraft did absolutely nothing wrong.

Once the RMA process started, it was fast and easy. Elecraft sent me a confirmation once the item was received but I didn’t hear anything else until the day it was shipping out almost a week later. Since I’ve never dealt with returning a radio before, I felt that I had no idea what was going on or even if the radio has been touched by service. When Elecraft got back to me, it was shown that the PA Driver chips were replaced. I wished for a little more detail into what could possibly caused the replacement as to avoid it from happening again.

Months later and with very LITTLE use, the plastic knobs started to crack. After contacting Elecraft, they moved quick and got the replacements I need. Even though it appears this was a common issue, I was a little more impressed with their service this time around.

Amplifier over 2M module

When the KX3 first rolled out, a 2M module was incorporated into the design but wasn’t available. Due to the fact that I enjoy doing SOTA on VHF, I was excited that there was going to be a 2M option at some point. That means less equipment that I’d have to carry and something better than the Chinese radios that I’ve been using. However I was very disappointed when they decided to design an amplifier for a radio that was designed to be a QRP portable rig. I get why they did it. Not many people really care about QRP SSB on 2m or 2M in general when it comes to portable operations. They would rather have something that would allow for 100W while mobile or at the home while taking advantage of a really good receiver. It turns the KX3 into a dual purpose rig. I would have rather seen the 2M module first.

Even though at times, it may seem I’m very critical of Elecraft, It’s because I want them to succeed. They make good products, they’re very interactive with the community and they’re based in the United States. I just want them to improve so they can be on the same production level as the “Big Three”. I honestly think it’s possible.

Final Thoughts

Using the KX3 on top of Mt. Tom, Holyoke MA

When I decided to purchase the KX3, I thought I would be taking up adventures like climbing mountains, hiking, going to parks and testing the limits of QRP. It didn’t really happen. Those times I got to get out and played radio, the KX3 performed very well. The very low current draw allowed me to use full power (approx 10W) using a Hobby battery (Turnigy 2200mAh 3S 20C Li-Po 11.1v) that lasted for at least an hour before turning back the wattage (to 5W) when the battery voltage dipped below the 11vdc threshold (time will vary depending on duty, temp and mode). The radio is easy to pack and deploy. If there are trees tall enough in the area, I can hang a dipole and get on the air within 10-15 minutes.

Even though there are cheaper alternatives, I think I’ve made a wise choice. If I ever decide to go portable, It’s there and ready to go and it just works.

SOTA Pack consisting of KX3, G5RV Jr and End Fed

I would recommend this radio to others under certain circumstances. If you’re just getting into the hobby, I wouldn’t suggest it unless you have the money for radio and amplifier or you live in a restricted area where a base antenna setup is just not possible and would have to go portable/mobile. QRP is a rewarding challenge but frustration will set in when your in a pile up with a 5W signal and a compromised antenna.

I was given two popular antennas to use for a decent amount of time. I figured to try them both out and share my feelings about each one. I was given the Arrow Satellite II from Arrow antennas and a dual band Log Periodic from Elk Antennas. We’ll look at each antenna individually and then compare them to each other.

Arrow Satellite II

Whenever someone mentions working amateur radio satellites (reapeaters in the sky), the Arrow Satellite II is almost always mentioned. It’s been mentioned so many times that I wanted one. However like most hams, I’m cheap! If I feel that I can make the exact same antenna, I will try my best to do so. I tried looking for the plans for that antenna but couldn’t find them. I was bummed out until someone I knew (N1KXR) purchased a used one from another ham. This was the perfect time to take the antenna and dissect it.

The first thing I did when I got the antenna was to assemble it and PLAY! The actual assembly of the antenna was OK. The reason it’s called an ARROW antenna is because the elements are made from aluminum arrow shafts that are used in archery. The great thing about using arrows is that they are light and built to some strict specs.

I like that it’s light weight and that I can setup the antenna to either VHF or UHF or Both. The duplexer inside the handle is a big plus. I don’t have a spectrum/network analyzer or lab equipment to give you the in-depth specs of the antenna (I just wish I knew) but it shows good SWR on my bridge (meter) and it performs. The only thing I would do if this was mine is to use different color electrical tape (or paint markers) to identify the correct pairs of elements. I lined them up by height. I would also drill a hole in the handle (away from the duplexer) so I could mount the antenna to a tripod better. As I found with the PVC Tape measure yagi, It gets heavy after holding it for awhile.

Let’s Reverse It!

I wanted to make this antenna almost exactly the same way it was purchased. From using arrows shafts all the way down to the micro-duplexer that is in the handle. I didn’t want to drift far away from the original design so out came the 5ft vernier calipers and went to town remaking the entire antenna in CAD.

After putting all the dimensions back into CAD this is what I got. I would like to say it’s within .005″ and the antenna is possible to reproduce if you have access to a drill press, arbor press (can’t tell if the BNCs are pressed) and lathe (Or a good fixture for the drill press) as most of the work would be focused on the driven element/gamma match.

Is it worth making your own?

Even though I have access to some of the material, I wanted to look at as if I had nothing and had to go out and buy all the material. So I started calling around for quotes on material. The more and more I got into it, the price kept climbing and climbing.

Let’s start off with the Arrows. I wanted to use the same aluminum arrows just like the ones that are used on this antenna. I went looking for the Arrows they used based on the dimensions I got from reverse engineering. While trying to find these arrows I learned a lot about all the different types of arrows used in archery. When it comes to aluminum arrows, they use a 4 digit number system. The first two digits are the diameter of the shaft in 1/64″ increments and the last two digits are the wall thickness in 1/1000″. I found out that they are using 1716 arrow and the only ones I can find are by Easton (Easton Blues/Jazz) and they are not cheap. Just the shafts would end up being $60-$70. That doesn’t include the 8-32 Inserts.

The tubing, square stock and bar stock for the boom and gamma match would add up to approx $30.

So far we’re looking at least $100-$120 for the material and that doesn’t even include the micro duplexer. You can purchase the duplexer ready to go from Arrow Antennas for around $60 or you can make it yourself using the plans found on KI0AG’s Site that appears Arrow Antennas used as well. If you don’t have the means or equipment to make/etch your own boards then it will still cost a decent amount of money.

For me, It’s not worth building.

The price of material would meet or exceed the cost of the antenna if you were to buy it from Arrow. This doesn’t include the splitboom, duplexer and labor involved. As much pride as I take in building my own, it’s not worth it. I can buy the antenna already made for less then it would take to manufacture. I tried things like using 1/4″ solid aluminum rod to reduce the materials costs but now you are spending more time in labor in drilling and tapping for a 8-32 screw. A lathe would really help in this situation.

How does it perform?

I can’t get too technical because I don’t have any of the testing gear or the know how to give you exact figures. The following evaluation is just from my personal observations.

The way I received the antenna was in a tube with what appears to be the original plastic bag that separates the UHF and VHF Elements. Since this antenna is used, I am not sure how it comes from the factory. Assembling the Antenna is quite a challenge. The elements are NOT labeled! What I had to do was line up the elements by height and pair them together for both the VHF and UHF side of the beam. For me, most of the time assembling this antenna is spent finding out which element is which. This would be my only complaint about the antenna. However it can be fixed by doing a couple things. Buying multicolored electrical tape and put some tape on the elements and boom. You can also purchase or make your “Antenna” bag with pockets for each pair of elements.

Assembly is pretty much straight forward once you know what goes where, Just screw them together through the boom, hook up the BNC connector and you’re ready to go. I’d suggest the first time you put it together to check SWR and adjust the gamma match for optimal SWR.

I spent some time tracking Sats, hitting repeaters that I can’t normally hit with a rubber duck and some back yard RDF. The antenna performs, I was able to pickup some satellites like the NOAA and some Ham Sats and it performs just like you would expect. There is nothing much more I can say performance wise other than it works.

Pros:

Uses aluminum

Lightweight

Tuneable (Gamma Match)

Built in duplexor

Use either 144 or 440 or both.

Breaks down into a small area

Cons:

Elements not marked

Arrows can break

Built in duplexor

Very bulky when assembled

Hard to transport

If you noticed I put duplexor in both the pros and cons. The reason is because it’s great that you just one connection to the radio but you will have loss at the duplexor. I would assume the loss isn’t much at all so I wouldn’t be to concerned.

When you assemble both the VHF and UHF side of the beam, it turns into quite a bulky object and would be harder to transport inside your car. Not saying it’s impossible but you would most likely have to break down one band of the antenna.

Overall a great antenna and would recommend it to anyone that is serious about portable sat work, RDF and low power operations (<10W)

Elk Log Periodic

Whenever the Arrow antenna is mentioned, the Log Periodic by Elk Antennas is also mentioned and vice verse. The antenna is known as a log periodic which is a little bit similar to a Yagi. Instead of one boom, It uses two booms which the elements that are attached to each boom are 180 degrees from the elements on the other boom. In a simple way I can put it is that it’s a bunch of dipoles of different lengths. When the signal enters the antenna, it will find the best pair of “Dipoles” for that frequency and the other pairs help direct the signal.

Lets reverse it!

Well I didn’t. I didn’t think it was worth it.

The antenna is made with some quality parts. The Booms are thick walled aluminum tubing. They are spaced part using plastic spacers and plastic bolts and it has tapped holes along the boom with #10 screws to hold the elements. The boom is mounted/supported by two different grades of PVC tubing. The PVC used for mounting is schedual 40 and the other appears to be electrical conduit. The elements are also aluminum tubing that appears to have been either wet or powder coated with vinyl caps to protect the ends. They also have pressed in threads (10-32). They are high end tent poles. Included is a Handle made from PVC tubing that has a foam grip fitted to one side. This handle allows for portable ops.

Is it worth making your own?

I priced everything out as if you didn’t have any of this material laying around the house and you started from scratch.

4Ft Aluminum tubing for the boom – $25

12ft Aluminum tubing for the elements – $35

PVC for mounting – $10

Vinyl caps – $5

Stainless Screws/Nuts (Nylock) – $15

Plastic Screws/spacers – $10

SO-239 Chassis mount – $5

Total Materials cost – Approx $105

Just based on materials alone, It’s cheaper than if you were to purchase one.

For Me, It’s not worth building

Even though the materials are cheaper than what it’s being sold for, there is quite a bit of work that has to go into this antenna. One of the booms will have to be machined for a notch to allow the SO-239 connector to sit flush. There is also a LOT of drilling and tapping going on. That means you need a drillpress that is almost perfectly 90 degrees and fixtures/jigs available to drill nicely through round stock. If you don’t have the time or you highly value your time, I can see 4 or so hours in manufacturing and assembly. If you wanted to go all out and powder/wet paint the elements, then you are add more time and costs.

How does it perform?

Once again, I don’t have the equipment to give you a proper assessment of the antenna. The following evaluation is just from my personal observations.

I got the antenna mostly un-assembled in a bag. I am not sure how it comes from the factory as this is also a used antenna. Assembly is easy with this antenna. The elements and boom are marked with different colors. All you have to do is match up the colors and screw them to the booms (Yep, still calling it that), connect the coax and away you go!

I was able to receive some Sats, and hit some distant repeaters with my HT. I also mounted this to my simple TV rotor in my attic and used it with my FT-1900R.

I even did a night time SOTA activation with it. Worked quite well.

Pros:

Easy to assemble

East to transport when assembled

Dual band

No duplexor

Easy to break down

Can be semi permanent install

Can accept up to 200w VHF and 100W UHF

Cons:

Uses PVC

Coax has to be positioned correctly to avoid SWR issues

Even though the antenna works and does a great job, The use of PVC just makes me feel that the build quality is… meh. It has a home-brew feel to it, that’s all. When hooking up the coax, you have to keep at least 8″ of the coax 90 degrees from the boom as suggested on their website. In order to get the most out of this antenna, you would have to make some sort of fixture to mount the coax correctly which could be a hassle depending on how you’re looking at it.

Dueling Antennas.

Cue the banjos and setup the octagon because we have a fight on our hands. Well… Not really. There is no winner and there is nothing that would make one WAY BETTER than the other. They both have their unique features and they both pretty much perform equally in my book. I like the Elk because it’s not as bulky and can handle more power but I like the Arrow because it doesn’t use Plumbers\Electrical PVC and it’s easy to adjust. If push came to shove and I had to make a choice, I would lean toward the Elk. If they redesigned the boom holder/mount using something other than PVC tubing then I would prefer the Elk over the Arrow.

I decided to make a carrying case for the elk. I used outdoor canvas and my sewing skills are absolutely horrible. But it’s better than the nylon tent bag that was being ripped up by the screws that are sticking out of the boom. Now all the elements are organized and I have a pocket to put coax or a small handheld radio. The green tube in the background is what holds the arrow that was created by the owner of the Arrow. It appears to be a pool stick bag with a PVC pipe. It’s long because at the time, it was one solid length of boom

Here is a photo of both the antennas un-assembled. At the point of taking this photo, the Arrow still has a one piece boom. They both pretty much take up the space if the boom was split on the arrow.

Here is the duplexor that is located within the handle of the Arrow. Wasn’t going to cut the shrink wrap to show the circuit but it’s no secret. the plans are out on the internet.

Here are both antennas assembled. You can see that the Arrow is bulkier due to it’s cross polarization and it’s a bit longer than the Elk. But I will say that the arrow “Feels” lighter. I wouldn’t be holding either antenna for an extended amount of time.

Here is the “Split Boom” modification I did to the arrow antenna. This is available as an option from Arrow Antennas and I would suggest spending the extra money to have it done for you. What’s great is even though arrow sells a split boom model, they published the modification to make your one piece boom into a split. I followed the directions on the site except for the angle. I used a piece of 1/2″ plumbing copper pipe. I should have turned it down in the lathe as it was a really tight fit. Once I got the copper pipe a couple inches in the boom, I drilled a hole through the boom and tube and used aluminum pop rivets to secure the copper tube. Once I got the other end of the boom to slide on the copper pipe and meet the angle, I drilled a hole through copper tube using the hole for the first director element for the UHF side of the antenna. This way when you thread the arrows through the boom and tube, it will “Lock” the booms together. Nice move on arrows part.

Overall there is no clear winner. They both have their strengths and weeknesses. My personal preferance would be the elk even though I wouldn’t mind the arrow at all. Tasters choice I guess.

Even though I have yet to participate in any type of Radio Direction Finding (RDF) event, I find myself buying and building stuff for it. This time I decided to build an offset (active) attenuator as I think it’s a must need for RDF. When I was testing out my 3EL tape measure Yagi, I placed a transmitter on my property and tried to find it with a Yagi and found that it was near impossible to pinpoint the source as my radio was showing full scale and dead full quieting no matter where I went.

Since I’ve been reading a lot about fox hunting, I knew I needed an attenuator. However there are different kinds of attenuators that you can make or buy commercially. I wasn’t sure what to get at the time. I narrowed it down to the offset attenuator and the step attenuator. I went with the offset attenuator because it appears to be cheaper, easy to make and better than a step attenuator.

The attenuator that I went with was found on HomingIn.com’s Website. The article was writen by Joel Moell (K0OV) and explained in detail about the attenuator. What the offset attenuator does is “Offset” the received signal by 4MHz using a diode, oscillator and some other passive components. You are now listening to the signal away from it’s transmitting frequency. Your antenna and radio is no longer being overloaded and you’ll be able to get even closer to the signal.

It appears to be quite easy to build, even for me! So I went with it. The parts that are listen in the article are a little outdated

Here is an updated list of parts that I purchased. I usually use Mouser for components but I wasn’t satisfied with their shipping to the North East so I used Digi-Key with better results

Qty

Desc

Price

P/N

Source

1X

CAP CER 470PF 2KV 10% RADIAL

$0.23 ea

1286PH-ND

Digi-Key

2X

CAP CER 4700PF 50V 10% RADIAL

$0.30 ea

BC2683CT-ND

Digi-Key

2X

RES 2.2K OHM 1/4W 5% CARBON FILM

$0.10 ea

2.2KQBK-ND

Digi-Key

1X

RES 4.7K OHM 1/4W 5% CARBON FILM

$0.10 ea

4.7KQBK-ND

Digi-Key

1X

DIODE SMALL SIG 100V 200MA DO35

$0.10 ea

1N4148TACT-ND

Digi-Key

1X

OSC 4.0000 MHZ FULL SIZE

$2.49 ea

CTX774-ND

Digi-Key

1X

BNC FRONT MT RECEPT SHORT

$4.67 ea

ARF1064-ND

Digi-Key

1X

5K Audio Tape Pot

$3.49 ea

#271-1720

Radio Shack/In-Store

1X

Perf Board/PC-Board

$2.49 ea

Radio Shack / Instore

1X

SPST Swith

$2.49 ea

Radio Shack / Instore

Total project cost: Approx $8.00-$18 USD

Making Sure Everything Works

Before putting it on any type of board I wanted to make sure that It works. I never really messed around with making electronic devices from a pile of parts. I put the entire project onto a breadboard following the schematic as close as possible

Here it is being tested out on the breadboard It went together pretty easy. I used a voltage meter to make sure the correct voltage is coming out of the LM7805 regulator. I was seeing around 5V

Here is a video of it in action

Now that I know it works, it’s time to transfer the design to a more permanent home. I wanted to compact it as short as possible to get it to fit into a small PVC box. Since I had a PVC box I wanted the board to go into, I measured a piece of perf board and cut it up

After cutting the board, I laid out all the components and attached all the wiring I could from underneath the board

Here its with most of the stuff attached.

Here is the Top view of the board. I had to use some jumpers (red and green wires) to get some of the components to make contact.
The black wires you see leading away from the board are for power and the adjustable resistor. I tried to test it out at this point to make sure it works before adding the coax and other things but It turned out not to be worth doing. But I did check the circuit wiring a couple times to make sure.

Final Assembly

Getting it jammed into the small box was going to be difficult. I knew right away that I wouldn’t be able to fit the 9V battery and the circuit board into the same compartment without using a larger box.

Here is the PVC junction box with the circuit board, switch, POT and cabled jammed into it. I had to have shave some of the flange off on the cover as the Pot is almost the same size as the Inside dimension of the box.

To solve the battery issue, I fabricated a small aluminum box that can hold a 9V battery. I drilled a small hole in the side of the PVC case to route the power cable through. In the above picture you can also see the on/off switch and adjustable pot. I mounted the switch sideways to avoid any accidental switching even though it’s still possible.

Here is the fully assembled antenna. The PVC junction box is also used to mount the grip handle. This way most of the weight is sitting on top of my hand instead of out on the boom. I also didn’t want to put any kind of electronics/metal between the reflector and driven element. Not sure if it would make a difference but I think it’s better off this way

Lessons Learned

I learned a lot while making this attenuator. The circuit was simple enough to where I can understand what is going on.

If I were to build another one, I would make some changes to make it even better. The big problem is that the coax runs from the driven element straight into the attenuator from inside the PVC. This doesn’t allow me to swap out antennas. What I would do is put a BNC connector sticking out of the PVC box and have the coax come out the boom to make the connection. I could just make an attenuator that is seperate from the antenna but that is just another bulky piece of equipment to carry around. I wouldn’t want to attach it directly to the radio because I think it would put strain on the connector that is in the radio.

You also can’t TX using this antenna. If you do, you can kiss the diode and possibly other parts goodbye. I would try to install some kind of switch that would allow me to TX but I’ll just carry an extra antenna or extra radio for now.

I’ve been wanting to do a SOTA (Summits On The Air) activation for quite some time and I finally had the chance to go so I took advantage of it. For those who don’t know, SOTA is “Summits On The Air”. Take your equipment, climb a mountain (or hill) with your gear and make at least 4 contacts in order for it to be a successful activation. What’s great about SOTA is that it gets you off your butt and go outdoors. Another great thing about it is that there is a website where you are allowed to self spot so at least others know where you are. After you are done you upload or enter you logs into the website and you can start competing with others in the area and possibly get awards.

In my last article, I made a 3EL Yagi using a tape measure that I didn’t use other than waving it around like a mad man in my back yard. I built the Yagi so I can participate in outdoor activities like radio direction finding and SOTA. So for the past month or so I’ve been itching and looking for any excuse to use this antenna. Nick (K1MAZ) mentioned that he was going to activate Mt. Norwottock after he gets out of work alone. Since my night was free and available, I contacted nick to see if I can tag along which he said sure.

Since this was last second, I ran around the house trying to locate the things that I would think I need for a SOTA activation based off of what I’ve read from other peoples SOTA adventures. I took along my Yagi, Two 2M HT’s, adapters, lots of tape, extra stubby antennas, multi-tool, knife, stuff to keep me warm. Away I went into the dark to drive to “The Notch”.

Here is a map of the State park. The line is red is that path from the visitors center to the summit.

Here is the APRS map of our hike. You will notice that we sort of took a wrong turn. Trail markers are a lot harder to see at night! After we fixed our headings, the climb started and I realized a couple minutes into the “climb” that I am out of shape. I kept stopping, huffing and puffing while Nick was having no issue with the climb. I wasn’t sure if it was all due to being out of shape or wearing very thick clothing .

Once we reached the summit, I was hot to trot so I immediately got the Yagi going and left Nick to assemble his HF wire antenna. I should have helped him but I was a little to excited and wanted to get on the air right away. After making the bulk of my contacts, I’ve stopped to help him finish installing the antenna.

This was the setup that I was using. My homebrew 3EL Yagi and the Wouxun kg-uvd1p handheld.

Since there was cell/data coverage on the summit, I spotted my self on the local clubs FaceBook page and thought I spotted myself on SOTAwatch. Got on 146.520 Mhz (AKA National calling freq) and started calling CQ. As there is little to no activity around here on 146.520, I decided to stay on that frequency as it was not causing any harm. Not even a minute of calling CQ, I was contacted by ED (KB1NWH) from his QTH 22Mi away from my location as well as Mike (N1TA). At the point I was assuming that they and some of the SOTA regulars in the area were going to be my only contacts. I was wrong… One of the people that worked me or saw my post on Facebook went on the local repeater and announced that I was up there. That opened up the flood gates and I worked the following

AB1RS – Rich

KB1PWH –

WD1S – James

W1MSW – Matt (SOTA Jerks)

N1FDC – Phil

KB1VPN – Jake

K1YO – Bob (Mobile)

KK1W – Jim (SOTA Jerks)

WI1N – Charles

WC1Y – Rory

KB1JFQ – Chuck (SOTA Regular)

WW1X – Rockwell (SOTA Regular)

N1KXR – Rich

A total of 15 Contacts on VHF.

All these people coming out to work me made all the troubles I had getting up there worth it. I was going up there thinking that I wouldn’t have enough contacts to make the activation count but thanks to those listed above, I now have 1 activator point.

I’ve learned a lot by this one trip. The tape measure yagi turned out to be a success! Almost everyone that contacted me on VHF was strong and DFQ.

I plotted out all the contacts I made based on their address on QRZ.com, Two of them were mobile stations so I just put markers to area where they reported they were.
Everyone was pretty much “From The Valley” and all contacts I’ve had were crystal clear. I had a backup two meter radio and I should have used it to compare using the rubber duck to using the yagi but that thought escaped me.

HF Side of Things

Nick was more interested in the HF side to the hike. He brought along his FT100, MFJ Tuner, G5RV and coax. When we reached the summit area, Nick when right to work putting up his antenna in the dark. He didn’t get the antenna as high as he wanted it (8-10ft off the ground) but used it anyways. Once everything was set, Nick spotted then went on the air.

Here is a little video I took.

At first all the locals were calling and then some of the SOTA regulars started contacting him as well.

Between 80M and 40M, Nick had 15 contacts and I had 7.

Lessons Learned

This was just a quick last minute thing for me so I didn’t have much time to plan. I quickly gathered anything that would fit in my pockets of my cargo pants and was more worried about staying warm than anything else.

Even though the Yagi I was using didn’t weigh much and it didn’t give me an issue during the climb, It started to “feel” heavy while I was using it. Holding that and the radio at the same time made logging contacts very difficult. Not sure if it was me or the cold weather but the radio kept changing frequencies which made things a little more difficult. I am going to modify the yagi so I can put it on a Tripod and I am going to make it so the radio can be mounted to the tripod as well and use a speaker/mic to make contacts.

Overall I had a great time and I want to do it again with VHF. If I keep doing it, I might pickup some portable HF gear.

After seeing a lot of articles written about making a three element Yagi using PVC and a tape measure, I was interested but not excited about it. That was until I made a QSO with K1MAZ (Nick) while he was doing a SOTA Activation. I decided to try to make contact with Nick on VHF as it was spotted on the SOTA website. Nick was on top of Burley Hill in Union CT which is about 30mi from my QTH. He tried using his stock antenna on his Yaesu Handheld but it’s just a little too far out of range. I knew someone was trying to get in but there was no copy. A couple of minutes later I hear him again, but it sounded like he was in front of my house. He was S9+ and very clear audio. After meeting up with him I asked what antenna he used and he said that he was using his Tape Measure Yagi. I was somewhat amazed that it worked that well.

Now I want to make this antenna. It appears to be real easy to make and requires only hand tools. I ended going with a mixture of three designs

The first design I went with was from WB2HOL which appears to the origin of this particular antenna. It’s designed to be a RDF (Radio Direction Finding) antenna. It could also be used in portable operations like SOTA or Field Day. I obtained all the dimensions needed from his website.http://theleggios.net/wb2hol/projects/rdf/tape_bm.htm

I got the boom design from the Camden County Radio Society’s website which is slightly different from WB2HOL. It replaced the tee used by the director with another cross tee and added a 5″ stub. I have no particular reason why I went with this book design. I just liked it and it avoids adding a different part even though it’s no big deal.

Is the choke/balun needed? I’m not experienced enough to give you a yes or no answer. I decided to use it because it wasn’t going to cost me anything to do it. If it didn’t work our or was causing an issue then I can just simply un-wind it.

I am not going to go into detail about making the beam as it’s already done for you in the those articles that I linked to above.
However I will provide a detailed blueprint that is a little better than what I’ve seen out there.

I tried as best as possible to get the exact dimensions of the PVC caps and cross tees but I found that the dimensions vary between manufacturers. That will explain the 0.060″ (1.5mm) differnce in element spacing as noted on the print.

Along with the instructions on the blueprint, I would like to share some of my personal experiences when it comes to building and using the antenna.

Working with PVC Tubing

I didn’t have a PVC cutter as I rarely do PVC work. I also didn’t have a vice or clamp setup to use a regular saw or sawzall with. I ended up using a tubing cutter that is normally used on copper tubing for plumbing. It worked but it wasn’t pretty. It pushed the PVC to form a flange or lip around the entire diameter of the tube. I had to use a sander to remove the burr/lip.

PVC Cut into lengths

I also decided NOT to use PVC primer and cement. The parts fit together so tight that I didn’t even bother using it.

Antenna Boom Dry Fit – PVC was so tight fitting that I didn’t bother using glue

Tape Measure Sharpness

The tape measure is somewhat sharp along the long edge. It’s not razor sharp but it’s sharp. Cutting the tape measure creates a real sharp edge. You can combat this by either wrapping the exposed edge with electrical tape or cutting a chamfer (corner) or both. I’m going to use a product call “Plasti-Dip) and coat the tips of each element with it.

(Chamfering the corners and sanding down the points)

Hopefully you will be careful running around with the beam. Doing this will make things just a tad bit safer.

I’d would either dismantle or cut out the bad sections of tape. If you already have a 1″ wide (or bigger) tape measure, I’d suggest buying a new one and cut apart your old one. I’ve notice coating usually wears out within the first couple of feet. My suggestion would be to start cutting the tape up from the oppisiet end.

Soldering the Hairpin and Coax

There is also an issue when it comes to soldering the tape measure. If you have normal flux core solder, you might have a hard time soldering the wires to the tape measure to where it won’t stick. I ended up using a liquid flux that is commonly used in the plumbing/welding industry. It’s an acidic flux that works great.
After grinding away the paint/coating on the tape measure, I put just a teensy drop of flux on the exposed metal of the driven elements. After soldering the hairpin match and coax using a 100W iron, I took it over to the sink and washed off any left over residue that was still on the tape. I’ve been told and I’ve read that using this type of flux is pretty corrosive and will eat away at the metal it was applied to causing a bad connect. So please be careful. After a week of playing around with it, I have not noticed anything.

Running the cable through the boom.

You will notice that I drilled some holes extra holes. I want to run the coax through the center of the boom, have it come out to start the coil and back through. I did that so the cable couldn’t drag across or get snagged in the reflector and to provide a little more security with the coil. It’s not a big deal but I found it to be cleaner than having it zip-tied or taped to the boom.

Cable Through Boom

Prices Involved

You can build this antenna for under $20. Since I work in trade where a lot of people accidentally cut off or destroy their tape measures, I have quite the collection of tape measures.

If you already have a 1″ wide or bigger tape measure in your tool box, I’d suggest on purchasing a decent tape measure and use your old one for this project. When it comes to using used tape measures, I would make my cuts starting from the other end of the tape. Most used tapes have lots of wear and tear on the first 12″.

Also don’t cheap out and get regular steel and electrical grade PVC conduit. The clamps will rust and the electrical PVC has a thinner wall and will easily flex. It may not happen right away but time will take it’s toll. I know it’s a cheap antenna but it would be more cost effective in the long run.

End Result

Well Did it work? I would say so, I don’t have an analyzer to tell you for sure. I hooked up the antenna to a SWR meter (bridge) and was seeing 1.2-1.5 on the meter. I went out in the back yard of my house and I’m sure my neighbors think that I’m training to be a JEDI fighter or something with the way I was waving the antenna around. I ended up hitting a couple of repeaters that I couldn’t normally hit with the stock antenna

Here is a video I made really quick to show it in action

Nothing exciting but it was fun.

Here is the complete setup. I gave myself enough slack on the coax incase I decided to mount the yagi on a tripod.

Here it is with the elements folded up. I would do this before a fox hunt so I can place it in the back of my truck

Here it is folded up for extended storage. I use the clamps that hold on the driven element to secure the tape measure to the boom

Here is a plot of the Yagi using the miniVNA Pro. Testing conditions involved hooking the calibrated analyzer to the end of the feed line and taking multiple readings while holding the antenna in my office. Increasing the gap lowers the center frequency.

Overall it was a really fun build. It didn’t require any type of heavy equipment or tedious work. I have a feeling that running around the woods with a tape measure will end up with crimped or broken tape measure. However it would be much better that running around with 1/4″ (6.35mm) aluminum rod. Replacing the director and reflector would be easy as cutting the tape measure. So fart so good!

I am sure some of you have been hearing the letters RTL-SDR come up more often. At the time all I knew was what the SDR part meant (Software Defined Radio) and didn’t really care about the subject. After hearing more and more I decided to see what all the buzz was about.

The company Realtek (sounds familiar?) designed an IC chip called the RTL2832/RTL2832U (USB 2.0) that was originally used by electronics manufacturers that made DVB-T (Digital Video Broadcast – Terrestrial) receivers. These devices will display Digital TV signals from nearby TV stations (Remember the whole Digital TV upgrade that made older TV’s useless unless it has a converter) as well as digital FM radio onto your computer/laptop. The actual RTL chip demodulates the signal, cleans it up and processes the signal using a built in ADC (Analog to Digital Converter). All the software does is display the information that is coming out of the RTL and it will also control the frequency and filtering of the signal through a tuning chip on the board. It’s way more technical than that but I’m just giving you the basics.

Someone found out that RTL chip with the tuner could allow you do sample/listen to signals from 64Mhz up to 1678Mhz (Varies depending on the tuner) which is quite impressive. These chips could also decode many different modulations and you can view/sample megahertz at a time. All of this for around $20 USD and some software. With some other tricks you can decode APCO25 (P25) or other digtal and digital type signals with this dongle.

What does all this mean to me?
In short terms you have a Software Defined Receiver (SDR) that you can listen and actually SEE any signals from around 64Mhz to around 1678Mhz at around 2Mhz at a time.

For example you can listen/watch a good portion of the 2M (Let’s say from 146.000-148.000Mhz) band and see all the conversations going on in that 2Mhz span. Depending on the software you’re using, you can filter just what you want to hear while seeing what else is happening . If you’re listening to a repeater, you can view the station on the input as well as hear and see the same station on the output frequency on 2M. If you tried to get the same features in a police scanner, you could be spending at hundreds of dollars.

Is this too good to be true? What’s the catch? Is this a Scam?
It does seem to be too good to be true but it’s actually true. For around $20 USD, you can have a VHF/UHF SDR receiver. I have a feeling the price will go up as retailers are seeing a huge increase in sales of these “Cheap” devices. There are some catches however. It doesn’t have the best filtering so signals could get cross and mixed in. You’ll sometimes hear “Birdies” and there are times where the frequency displayed is not correct to the frequency you’re listening too (So far I’ve seen if off around 6khz). Another issue is with the dongle itself, depending on the manufacture the cases don’t have really any shielding and the antenna connection and the supplied antenna is basically crap. At the time of writing this, there are a couple companies seeing the demand for these RTLSDR’s and are making units with the correct case and antenna connection. But for the issues it has and for the price they are being sold at the moment, it’s well worth having. It’s almost comparable to purchasing a FunCube dongle for around $190 that is similar even though I think the FunCube is better and helps support AMSAT.

Ok ok ok… You’ve sold me. How do I get one these $20 dongles?
This should be the only battle you have to do. Securing the Proper Dongle at the correct price. There are many manufactures of dongles that do almost the same things. You want to find a dongle with the correct RTL chip and the correct tuner chip. The Cat’s meow of Chipsets are the RTL2832U and the Elonics E4000 (AKA E4K) tuner chip. Why? I have no clue. Some dongles have this configuration and some use other Tuners like the Fitipower FC0013 and FC0012 that work also. Some of the differences are the Bandsplit of what frequencies the tuner chip can tune.

At the time of writing this, If you can get your hands on a EzCap EzTv668 (or EzTv666) with the RTL2832U and E4000 tuner then you are golden. However the company that designed and manufactured the E4000 is no longer in business and the company is now being liquidated. This means at this point in time the E4K is no longer being produced. Most companies are switching over to the FITIPOWER FC0013. So you want to make sure that you are getting a unit with the E4K. There are some ebay sellers that are claiming to ship dongles with the E4K but they are really the FC0013.
If you happen to get stuck with one, don’t worry. It will still work.

Here is a Ebay “EzCap EzTV668” screen shot of one I actually purchased on Ebay.

(Click to enlarge)

I purchased this from a seller on Ebay as well as one from Deal Extreme (DealExtreme.Com). The reason I purchased it from Ebay is the one I ordered from DealExtreme was taking way too long and when I contacted their customer service, I was told they were out of stock and could take almost another month for it to come in.

If you notice the Ebay Auction says RTL2832U and E4000 tuner… Well… This is what I got!

It’s a EzTv645 and it has the Fitipower FC0013. This dongle is NOTHING like the advertised dongle on Ebay.
I could have complained and returned it but as you can tell, I hacked it up already. I just wanted to warn you that you might not get what is advertised on Ebay.

I added a Pigtail with a PL-259 which voided any warranty (if any) it had. I wasn’t going to waste time with trying to return someone that was sold over ebay and shipped from china.
When soldering on the coax to the board. I messed up and used a powerful (too powerful) soldering iron without any grounding or ESD protection.

Here is a Video of the dongle with the FC0013 in action

You’ll see some of the signals being mixed and some other horrible stuff.
I am not sure if this is how it is normally is or damage done from my soldering job.
Also for some reason the video lost sync with the audio.

The dongle still works but it’s in the hands of my co-worker who would really have fun with this.

The very next day after screwing up the Ebay EzTV645 purchase, My order from DealExtreme showed up

After reading posts on Reddit of people saying their recent DealExtreme orders have the FC0013 tuner got me a little bit worried. I opened the dongle and is happy to see this

This is what you’re looking for. It’s the advertised 668 with the Elonics E4000 Chip (Little square chip to the right of the Antenna Jack) and the RTL2832U (Under the IR Sensor).

I dared not to touch this one with a soldering iron. For now I went to Radio Shack and got a couple connectors (PAL to BNC). I would suggest going on ebay and getting the correct adapters or if you have a really good soldering station, solder in a SMA pigtail and/or connector.

Here is a video of the new dongle

It looks and sounds much better than the one I purchased from Ebay. But I can’t tell you for sure since I hacked up the Ebay one before I can make a comparison between the two.

The hardware finally came in… What now?

You now have to obtain software to display the information from the dongle. At this point while writing the article, the best choice for RTLSDR software is SDR# (SDR Sharp). There are others out there depending on the operating system you are running. I’ve chosen SDR# because it’s really easy to setup and use (compared to some of the others) and it works on some other SDR hardware I have. Plus IMO it’s best choice for beginners like myself. If you do end up using SDR#, make sure to download the DEVELOPMENT (DEV) Version as well has ZADIG which will replace the driver that was automatically installed (or attemped) when you plugged in the dongle with the one that is needed to run in SDR#

That’s It!! It should be working. Tune around and have fun. If you’re using the antenna that came with the dongle, good luck! You will not pick up much with the stock antenna. I ended up cutting the plug off the antenna and soldering it to some RG-58 as to not mess up the board. You can also find adapters online and possibly at Radio Shack. The plug looks like an RCA but it’s really a “Belling Lee” (IEC 169-2) connector or PAL connector.

Here are some RTLSDR websites that were helped me out and are resources for this article.

Even though Field Day (FD) is weeks away, the planning of it gets me excited knowing that it’s near. Field day is the basically the main reason why I got my license. During my CB days, someone brought me to a field day hosted by the MTARA (Mount Tom Amateur Radio Assn.) on top of Mount Tom around 1995. I recall being on 14mhz using a Kenwood TS-440 and was making contacts all around the country. Compared to CB I was amazed about the contacts I was making considering I would never hear the stations, let alone make contact with them on CB. Field day was the kick in the ass to get my license and pretty much put CB behind me.

For those who don’t know what Field Day is, I would check out this website that would explain it in more detail then I could. It’s a emergency preparedness exercise where operators try to contact with as many other operators as possible. Even though you don’t have to, it’s encouraged that you bring your gear and communicate from a field, hence “Field” Day. A lot of local Amatuer Radio Clubs put on events related to FD to have fun and also promote Amateur Radio to the general public at the same time.

Last year I participated in Field Day with the Hampden County Amateur Radio Association running the digital station.

NT1K Doing Digi (Photo By: Frandy Johnson, N1FJ)

This year I will be running SSB on 40M (7mhz) with the HCRA again at Dufresne Park in Granby MA. If you are in the area. You should stop by and check it out. Go Here for more information